Telephone system



Oct. .21 1924.

H. H. IDE

TELEPHONE SYSTEM Oct. 21 1924. 1,512,101

H. H. `:DE

TELEPHONE SYSTEM Fld Jan. 20. 1919 5 Sheets-Sheet 2 EL/@H7021 ,3 Harry/57de. N 7

Hwy-'27557.

Oct. 21 1924.

H. H. [DE

TELEPHONE SYSTEM Filed Jan. 20, 1919 5 Sheets-Sheet 5 Oct. 2l 1924.

H. H. IDE

TELEPHONE SYSTEM Filed Jan. 20, 1919 5 Sheets-Sheet 4' Oct. 21 1924. 1,512,101

H. H. IDE

TELEPHONE SYSTE M Fi ed Jan. 20, 1919 5 S eets-Sheet 5 Ezbrneg lll,

Patented Oct. 2l, 1924.

UNITED STATES y y 1,512,101 PATENT OFFICE.

HARRY IDE, OF CHICAGO, ILLINOIS, ASSIGNOR TO KELLOGG SWITCHBOARD AND SUPPLY COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION O'F ILLINOIS.

TELEPHONE SYSTEM,

Application filed January 20, 1919. Serial No. 271,960.

To all w kom t may concern.'

Be it known that I, HARRY H. IDE, a citizen of the United States of America, residing in Chicago, county of Cook, and State of Illinois, have invented certain new anduseful Improvements in Telephone Systems, of which the following is a specification. y

My invention relates to telephone systems and has to 'do more particularly with automaticn or semi-automatic systems in which -switches are used for connecting a calling line to an idle trunk and one object of my invention -is the provision of an improved arrangement which embodies desirable features and advantages all in an eliicent, simple, economical manner, and in which the parts are so constructed and combined as to make them readily accessible for manufacture, assembly, adjustment and repairs.

A feature of my invention is the p-rovision of a switch of the non-restoring type, that is one which remains in contact with the trunk last used when disconnection is effected, and which will again seize the trunk last used when a call is initiated, provided the trunk in the meantime has not been seized by another switch and is in use at the time the call is made.

Another feature of my invention is a novel interlocking'mechanism for controlling the operation of certain apparatus and functions of certain relays associated with the switch.

Still another feature of my invention is the provision of a switch with a positive drive circuit that does not permit the wipers of the switch to stop on lbusy contacts nor to pass over idle contacts.

The novel features of the invention through the provision of which the abovementioned and other advantageous results are attained-will be explained by reference to the accompanying drawings in which like reference characters .in the several views denote like parts, and in which:

Figs. 7 and 8 illustrate combined off-normal and cut-off relay control mechanism in y Figs. 11 and 12 illustrate combined 0H- normal and cut-off relay control mechanism in another of its olf-normal positions;

Fig. 13 is a view of the wipers;

Fig. 14 is a sectional view along the line 14--14 of Fig. 13;

Fig.' 15 is a sectional view along the line 15-15 of Fig. 4;

Fig. 16 is a sectional View of the main shaftshowing its construction;

Fig. 17 is a sectional view showing the method of mounting the magnet coils;

Fig. 18 '.vhich comprises parts 1 and 2 illustrates diagrammatically an automatic telephone system including the line switch of my invention.

Referring now more particularly to the, structure as illustrated in Figs. l to 17, inclusive, the line switch of my invention comprises a mounting plate 2 to which are secured the operating parts of the line switch, and also a bank of contacts B. The said bank of contacts B cooperate with the wipers W, which latter are supported upon a shaft S. Plate 2 further supports a motor magnetl MM, a combined line and `interruptei` relay LR and a cut-off relay CO. Contact bank B comprises any suitable number of contact sets, each set including a private contact 4, a common contact 5 and line contacts 6 and 7. Twenty-five sets of contacts per switch is ay convenient number. The contacts are radially disposed between strips of insulation cloth 8 and 9. Strips 10 and 11 of micarta or other suitable material are placed between the conta-cts to. properly space and insulate them. Contacts 5 may be connected together to form a common for private contacts 4 or they may be used for other connections. Strips of insulation 14 are placed between the clamping plates 12 and 13 and the contacts. Bolts l5 with nuts 16 secure the Contact bank, as a whole, between plates 12 and 13.

To secure the bank to the supporting l posts 3, (which are fastened to plate 2),

I provide the lower plate 13 with ears 17 and 18 bent over parallel to theplane of said plate. Ears 17 and 18 and plates 12 and 13 have openings to receive posts 3. Bank B, as a whole, is slipped on the posts 3, and screws 19 which have screw-threaded engagement with the bridge portion of the .ears 17 and 18 are tightened to maintain the ybank B, as a whole, in its'adjusted position. Wipers 20, 21, 22 and 23 comprise two oppositely extending arms each, while the contact bank, with which the Wipers are operatively associated,I forms a semi-circle so that when one set of arms leaves the last contact set 4, 5,; 6 and 7, the other set of larms engages the rst contact set. Wipers 20, 21, 22 and 23 mounted upon the shaft S are suitably insulated therefrom, hub 24 being provided for carrying the wipers and the conducting rings v25, 26, 27 and 28'.. The wipers 20, 21, 22 and 23 are similarly constructed; for example wiper 2 0 has a ring-shaped body portion 203 .and two arms 20 and 202 havi`ng flared ends for contacting with the contacts 4. The pair of conducting rings 25 and 26 are properly spaced froml the wipers 20 and 21 by means of metal washers 32. Conducting rings 27 'and 28 are associated withl the wipers 22 ad 23 and properly spacedl from them by the metal washers-32. Spacer y washer and insulation washers'36 .suit-I ably space the various parts.. Screws '37' clamp the wipers and disks to the hub 24 and pass through insulating bushings 38 to engage shouldered portion 24 of the hub 24. I-Iuby 24 being provided with a central opening 40 for the purpose is slipped over shaft S and .When'the wipers areadjusted in alignment with their contacts respectively, the set screw 39 is tightened to hold the wiper unit W in its adjusted .position upon the shaft S.- The conductor rings 25, 26,' 27 andf28 form contacting surfaces for wiper-brushes 41, 42, 43 and 444, suitably mounted upon a stud 45 and insulated from the stud and from eachother by insulation washers 46. The wipers are held upon -the` stud 45 in any suitable manner as by means ofl the nut 47 which has screw-threaded engagement with a stud 45, the said stud 45 being fastened to the plate 2 by the screw 48. The wipers-41, 42, 43 and 44 contact respectively and permanently with the conducting rings 25, 26, 27 'and 28,-,which rings are in turn conductively connected to the wipers 20,21, 22V and 23 by washers 32. Thus Vthe wipers 20, 21, 22 and 23 are always conductively connected to terminals 412, 422, 432, and 442.

Sleeve 50 supported by late 2 serves as a bearing for the shaft S) and also as a bearing for the'ratchet 51 which operates to rotate the shaft S and the wiper unit MM W over the bank contacts: The sleeve 50 has its one end 50threaded and its other end provided with a anged portion 502, the said flanged portion 502 resting in a to secure the sleeve 50 and its supported parts in their adjusted position. A plate 57 is secured to the ratchet 51 byv means of the screws 58 and 59. The shaft S is provided with a squared portion 60 at its upper end which enters a square opening'6l in the plate 57. A suitable screw 62 passing through a suitable opening in the plate' 57 has screw-threaded engagement with a.

suitable 'tapped orifice in the squ-ared end 60 of the shaft S, thus connecting the shaft S to lthe vplate 57 so that when the ratchet.

51.is rotated, as will presently be described, the shaft S is also rotated therewith.

The motor magnet-MM, which is adapted to move the wipers, over bank contacts, includes a pole pie 63, -an armature 64, and a driving pawl 65. The 'electromagnet 66 is suitably secured to the pole piece 63 by means of a screw 67 which paes through a stud`68, the said screw having screw-threaded engagement with a suitable tapped opening in the core 69 of the magnet 66. The stud 68 through which 4the screw 67 passes serves as an adjusting means for the magnet 66 in a forward or backward direction, and has screw-threaded engagement with a suitable tapped orifice in the heel iron 63,

the other end of the stud .68 being provided with an integrally formed vhexagonal head 68. To adjust the magnetv 66, the screw 67 is loosened and the stud 68 turned to the right or left, as the case may be, to properly adjust the magnet 66 and when this adjustment is obtained, a lock nut 70 is tightened to hold the stud 68 in its adjusted position.

The-pole piece 63 has projecting ears 7l bent at right angles to the main part of the said pole piece, the said ears having suitable tapped orices which 4receive screws 72 to fasten the magnet 66, pole piece 63 and armature 64 as'a unit to the mountin plate f2. The pole piece 63 is provided wit projecting ears 73, bent at right angles to the main part of the pole piece, the said ears having suitable openings to .receive the pivot pin 74, which pivot pin 74 pivotally supports the armature 64 of the motor ma net The armature 64 is also provlded with ears 75 which -have suitable openings to receive the said ivot pin 74. A U-shaped member 76 is a so provided, the arms of which also have suitable openings for receiving the pivot pin 74. To pivotally support the armature 64 upon the pole piece 63, the pivot pin 74 is inserted through the openings in the ears 73 of the pole piece 63 and earsY 75 of the armature y,64, and through the'openings in the arms of the U- shaped member 76. One arm of the member 76 fits between one of the supporting ears 73 of the pole piece 63 and the adjacent ears of the armature 64.` A set screw 77 is provided and has screw-threaded engagement with the Yyoke end 'of the U-shaped member 71. The setvscrew 77 is used t`o sef curely hold the pivot pin 74 in place rela-- tive to the heel iron 63 and armature 64.

The armature 64 carries a pivoted driving pawl 65 which is normally held against an adjustable stop 79 by means of a leaf spring 80, the said leaf spring 80 being held in place by means of a screw 81. The adjustable stop 79 is pivotally secured to the mounting plate l2 by means of-a screw 82.. The stop 79 has anvenlarged end 79 provided with 4a slot 83, through which a screw 84 passes. To 'adjust the pawl 65 the screws' 82 and 84 are loosened and the stopl 79 is then moved about its pivot screw 82, causing the angular portion 792 to move to the right or left, as the case may be, vand when the proper adjustment is obtained, the screws 82 and -84 which have screwthreaded engagement with suitable tapped openings in the plate 2, lare tightened to hold itin its adjusted position. The armature 64 is held in its normal position by means of a coil spring l85, the said spring having its one end fastened to a pin 86 which is staked to the poleI piece 63, and its other end is secured to. an adjustable screw 87. The screw -87 passes through a suitable opening in the arm 88,which arm' 88 is integrally formed with the armature 64, the

said screw 87 being provided with an adjustable nut 89. The tension of the spring is t regulated by means of the nut 89. A set oit' contact springs J are associated with the motor magnet MM, the said sprin s being insulatingly mounted upon the poe piece 63 by means of the' screws 90,- which are suitably insulated from the springs J. A plate 91 is suitablymounted upon the face of the armature 64 by 'means o the screws 92 and is provided with an angularly extending arm 93, preferably integrally formed with the plate 91. The-.arm 93 is provided with Irubber buffers 94 which operate the spring sets J upon the attraction' of armature 64 when motor magnet MM is energized.- An adjustable screw stop, 95 is provided, whichv stop has screw-threaded engagement with the pole piece 63 and acts as a stop for the arm 93 when the said arm' is in its normal position. An adjustable screw 96 is provided and has screw-threaded engagement with the pole piece 63, and is position. 1

used for adjusting the normal position ofthe springs 97 and 98. A leaf spring 99 is provided and is ymounted upon the pole piece 63 by means of the screws 90, and a rubber .buffer 100 carried by the spring 98 is used to prevent the spring 97 v from contacting with spring 98. The springs 97 and 98 may be adjusted so` that they are sep-arated upon a partial attraction of the armature 64, or not until a full attraction of the armature 64 takes place. This adjustment of spring 97 and. 98 of magnet'MM is for the purpose of timing the instant at which the line relay LR has itsecircuit interrupted, as will be more fully hereinafter described.

The pawl 65 is adapted to engage a tooth of the ratchet wheelv51 upon each actuation the plate 2. AThe stop 101 may be moved vforward or backward as the case may be,

and when the desired adjustment is obtained` a nut 103 having screw-threaded enjgagement with the stud 101 is tightened to securely hold the stop 101 in its adjusted The cut-oft relay CO includes a pole piece 104, an electromagnet 105 and armature 106, the said magnet 105 being mounted upon the heel iron`104 by means of a nut 107 which has screw-threaded engagementy with the threaded portion of the core 108 of the magnet 105. The pole piece 104, magnet 105 and armature 106 as a whole aremounted .upon the mounting plate 2 by means of the lscrews 109 vwhich pass through suitable openings in the angular portion of the pole piece 104, which screws havesffrew-threaded engagement with suitable tapped orifices in the mounting plate 2. The armature 106 is pivotally supported by meansof'the pivot pin 110 which pin 110 rests in a suitable groove cut in the face of the armature, and a retaining clip 111 secured to the face of the armature 106 by means of the rivet 112 is provided to retain the armature in place. A set ofcontact sprin s L are associated with the cut-olf relay C and are insulatingly mounted upon the heel iron 104 by means of the screws` 113, the said springs L being operatively associated with the armature 106 but insulated therefrom by means of the rubber buffers 1.14 and actuated by the armature 106 upon the energization of the cut-o relay CO.

I provide a set of oit normal contacts ON insulatingly mounted upon an extension 104 ofthe heel iron 10,4 by means of the screws 115. The movement of the ofi normal contacts ON' is jointly controlled by relay LR and the cut-off relay CO, as will` presently be described. An armature-shaped member end of the extension 104 of the heel iron 104 by means of the pivot pin 110 of the armatureI of cut-off relay OO. A bracket 124 suitably fastened to thev mounting plate by means of the screw 125 is provided for pivotally securing a latch 126 by means of a pivot screw 127. The leg 128 of the armature-shaped vmember 116 is provided with a shoulder 129, and the latch 126 is provided with a notch 130 into which the shoulder rests, its edge 131 engaging the side 132 of the notch 130 retaining the armature-shaped member 116 in a position as clearlyillustrated in Fig. 8 to hold the springs 119, 120,

- etc., of the off-normal contacts ON in their normal position as also illustrated in Fig. 12. A line relay LR is suitably supported by va bracket 133 secured to the plate 2 b .means of thescrew 134. The line relay L is secured to the bracket 133 by means of a nut 135 which nut 135 has screw-threaded v engagement with the threaded extension of the core of the relay LR. The relay LR comprises a 4 heel iron 136, an electromagnet 137 armature 138 and a pair of interrupter spri H for purposes as will-be more fully 'hereinafter described.

An arm 141-secured to the armature 106 of the cut-ofi' relay CO in any suitable manner as -by,means of the rivets 142 isoperatively associated with a latch 143 which is also pivotally supported on the bracket 124 by means ofthe pivot screw 127, the said arm 141 being also operatively associated with the armature-shaped member 116. The members 126 and 143 lie adjacent to and parallel with each other. The latch 143 is provided with a notch 144 at its forward end in which the forward end of the arm 141 rests for purposes as will presently be described. When a call is initiated, the

line relayvLR is energized, bringing about the attraction of the armature 138. Arm 145 secured to the armature 138 by means of the rivet 146 is moved in an upward direction and its extension 145 engages the angular extension 126', preferably integrally formed lwith the latch 126. This causes the latch 126-to be raised and when the face 132 of the notch 130 passes beyond the edge 131 of the shoulder 129 of the member 116, it releases the said member 116 allowing it to rotate about its pivot,

, permitting the off-normal contacts ON to assume their alternate position, as clearly illustrated in Fig. 10. When in this position the edge 146.0f the latch 126 rests upon the edge 147 of the shoulder 129. The latch 143 is also raised due to the extension 126l l passing under the latch 143 so that when the latch is in this position, as clearly illustrated in Flg. 9, the arm 141 is clear of the notch 144 in the forward end of the latch 143.

its armature 106 carrying the arm 141 with it, and the said arm 141 in its movement engages the leg 128 of the'armature-shaped member 116 and rocks it about its pivot. The line relay LR in restoring allows the extension 145 o f the arm 145 to disengage the extension 126 of the latch 126. The movement of the member 116 continues until the edge v131 of the shouldered portion 129 of the leg 128 passes the edge 132 of the notch 130 so that when in this position, the latch 126 rocks on its pivot allowing the shoulder 129 to again rest in the notch 130,

as clearly illustrated in Fig. 12. The buffer 118 due to the rocking movement of the member 116 engages the spring 122 of the off-normal springs-ON to move them back to their normal position, vand as the edge 131 of the shoulder 129 engages the edge 132 of the notch 130, the off-normal contacts soy ON are locked in their normal position until another energization of the line relay LR. The cut-off relay CO upon its energization shifts its springs J to vtheir alternate posi- 1 tions and the latch 143 is in such a position that its bottom edge 148 rests on the upper edge 149 of the arm 141 as clearly illustrated in Fig. 11. Upon the restoration of the cutoff relay CO, lts armature 106 restores, the arm 141 moving therewith so that when its edge 150 passes the edge 1.51 of the notch 144 of the latch 143,. the said latch 143 rocks on its pivot and again allows the ar m 141 to rest in the notch 144 of the latch 143.

Now should the line associated with the cut-olf relay CO be a called line, the said cut-off relay CO will be energized, but due to the arm 141 resting in the notch 144 of the latch 143 (Fig. 7 the movement of the armature 106 is limited by the amount of play that arm 141 has`in notch 144 (Fig.

7), as hereinafter explained. Y

A retaining pawl 152 is pivoted to late 2 by screw 153 and engages a tooth o the ratchet wheel 51, and is thus yieldingly held by leaf spring 154 fastened to plate 2-by screw 155. Pawl 152 retains the wipers W in engagement with a set of contacts as selected bythe switch. A condenser K is mounted upon plate 2 by means ofl a bracket 156 secured to plate 2 by screw 157.

The circuit 1n Fig. 18, parts l and 2, shows a calling substation A connected to circuits of an individual line switch C, which is the switch of my invention, and selects an, idle rst selector D. The first selector D selects an idle connector E, and the connector E connects to the terminals of the called substation F which has its line switch C similar to C. The substation A has the usual talking apparatus and a calling device CD to send impulse sets' to o erate the switches D and E to select t e called substation F, which is similar toA.

Line switch C of my invention may have twenty-five contact sets, and the circuit as shown at C is adapted to work with the switch structure described and illustrated in Figs. 1 to 17, inclusive. The switch structure for the iirst'selector D and connector E may be the same as illustrated and described in my application, Serial Number 175,364, filed June 18, 1917, issued as Patent No. 1,402,936, Jan. 1'0, i922.

Assuming. now that a call is to be traced from the calling substation A to the called substation F, upon the removal of the receiver by the subscriber at the calling substation A, line relay LR of switch C energizes by current from battery, through relay LR, contacts 97, normal contact 123 of the off-.normal contacts ON, normal contact 177, through the substation, back to ground lat normal contact 178. Wipers 20, 22 and 23 always rest upon the set of contacts 4, 6 and 7 last used, and assuming the `contacts upon which the wipers now rest are busy ldue to another subscribers line switch having selected .the iirst selector last-used by the subscriber A, the engaged private contact will be grounded. Energized relay LR assume their alternate positions.

'tacty set.

l current from batterythrough said magnet,

alternate contact 17 9, wiper 20 to the ground atthe busyprivate contact 4, and magnet MM steps wipers W to engage the next con- Mafgnet MM energizing opens the energizing circuit for the line relay LR at 97, and relay LR restoring opens contact 17 9 stores.

in the circuit of magnet-ltIM which re- Should the contacts now engaged by the wipers be busy, line relay LR energizes by current through normal contact 97, contact-s 121 and 122 to rthe ground vat busy `contact 4, and again closescontact -17 9, lener- '.gizing magnet MM as before described.

i tered. Ma vno gn The linerelay LR and magnetlilM are thus alternately energized and'de-energized,mag net MM stepping wipers 20, 22 and 23y from one set of contacts tothe next as long as busy, i. e. grounded, contacts arev encounet MM alternately opens and,

closes contact 182 and thus a vibratory circuit is closedthrough winding183 of cutoi relay CO to ground through contacts 119 and 120. The winding` 183-'of relay CO is of high impedance, and as motormagnet MM energizes vand de-energizeswith great rapidity, the said winding 183 of relay CO does not effectively energlze during the time that the magnet MM is operating. The ground at contacts 1.19 and 120 is connected to the lines private normal contacts 188 at the connectors having access to it to render such contacts busy. AV Vhen an idle private contact 4 is encountered, relay LR and magnet MM remain unoperated and the prolonged closure of contact 182 now eifectively energizes 'the Winding 183 'of relay C() by current to ground through contacts 119 and 120. The relay CC now closes its make-before-break contact 189, energizingits winding 190 by battery through said contact 189 to ground \Ithrough contacts 119, '120, momentarily reenforcing the, initial actuating force ofthe relay. Relay CO upon energization attracts its armature 106 and the arm 141 carried thereby engages the member 116 and causes the oit-normal contacts ON to again assume their normal posi-tion.' (See Fig. 12). The shoulder 129 of the member 116 now again rests in the notch 130 of thelatch 126 to again lock the'contacts ON-in their normal position. Contacts y119, 120, opening, open the circuit of relay CO, but said relaybeing slow to release is held up momentarily until a substitute circuit'is established for the f said relay CO, as will Apresently be described.

The circuit which is momentarily closedy through winding 190 is opened upon the full attraction of the armature, as will be observed.

Therelay CO having energized, its contacts 177 .and 178 assume their alternate gaging the contacts of the idle first selector D, impulse relay IR, at D energizes, circuit being traced from battery through conducand tthro-ugh relay 'IR to ground. Closed alternate contact 195 of relay IR energiz'es relay 196 by current from battery, through,

the upper winding of relay 196, contact 195, to groundat normal contact 199 of the primary off-normal contacts PON. Relay 200 position, and the wipers of switch C now en- L is also energized, over a circuit extending from battery through' the upper winding of said relay 200, alternate contact 195, to ground at normal contact 199. Relay 196 upon energizing 'closes a circuit through the upper winding of relay 200 through alter'- nate contact 208 of relay 196. The closing of alternate contact 201 of relay 200 establishes a substitute energizing circuit for relay CO of the line switch C before it has had time to de-energize, said circuit being traced from batt-ery through upper winding 183 of re-l lay CO', normal contact 182, conductor 186, -alternate contact 202, contact 20-4, conductor 203, alternate contact 204, to ground at f ing of contact 179 of relay LR does not energize magnet MM since there is no ground on contactv 4 and the magnet MM remains inert. The cut-off relay OO is immediately energized to ground at contacts 119 and 120, restores contacts ON asy before described, and the relay CO is held energized over the circuit to ground at D, as already described. Thus switch C only travels when its wipers are in engagement with a busy trunk when a call is initiated.

An idle first selector D having been seized as just described, and assuming that Athe number of the called substation Fis 345, the subscriber A actuates the calling device OD to ,send three impulses of current over the line, which impulses bring about three rapid de-energizations and ener izations of the im ulse relay IR; `"The primary magnet PDE is energized and de-energized three times due to the closing and opening of normal contact 195 of relay IR (circuit being traced via 206, 207, 195, 208), which magnet operates to step the Wipers 209, 210 and 211of the first selecto;` D in a down- War'd primary direction to the third group of contacts, thus selecting the three-hundreds group of connectors. After the last impulse, the relay 200 de-energizes,V due to,

a'circuit being closed through the lower Winding of thesaid relay .200, normal contact'212, alternate contact 213 of relay IR.-

and alternate contacts 214 and 199. The

said primary ,off-normalr contacts ,PON move to their alternate positions 'upon the first step of the Wipers of the first selector D, and the energizing circuit for the lower Winding of relay 200 just mentioned is closed 'upon the first step of the Wipers off normal, but the relay 200 does not deenergizc during the sending of impulses, it being differentially Wound and only receiv= ing short impulses of current through its neutralizing Winding during the impulse operation of 1relay IR. As soon as tlie above-mentioned circuit through 'the lower Winding of relayr 200 is steadily closed, the

lower or neutralizing Winding ybuilds up .and the sa'id relay Vper-mits its armature to retract. x The o ening` of contact 201 disbconnects ground om conductor 203 atJ` this point but -a substitute ground from alternate contact 199 of the primary olf-normal contact PON is vsubstituted before Isaid relay 200 de-energizes, to keeplcontact 4 busy and for other apparent purposes. Differential relay 196 is not de-energized during the rapid operation of relay IR, although rapid impulses are transmitted through its lower or neutralizing Windin due to the construction and adjustment o? the said relay 196. Upon the de-energization of. the relay 200,`an energizing circuit for the relay 215 is established from battery, through normalcontact. 216 of relay T, normal contactv 217 normal` ycontact 218 of the secondary off-normal contact SON, normal Contact 201, alternate contact 204 to ground at 199, and relay 215 energizes secondary magnet SM by current from battery through said magnet SM to ground at contact 219. Secondary magnet SMsteps the Wipers 209, 210 and 211 one step in a rotary or secondary direction to engage the first set .of oontacts 220, 221 and 222, and the opening of normal contact 217 at magnet SM de-energizes relay 215. Contact 212 opens the circuit of the lower Winding of relay 200 which energizes again.- Relay 215 opens contact 219,. de-energizing secondary magnetA SM.

Upon the rst step of the Wipers 209, 210 and 211, the secondary off-normal contacts SON assume their alternate position, opening the initial energizing circuit of the relay 215, and should thefprivate Wiper 209 of the first selector D engage a contact' leading to a busy connector, a substitute circuit is established for relay 215 traced from batteryA through the Winding of the relay 215, normal contact 216, normalcontactz 217, .alternate contact 223, alternate-contact 224 and wiper 209 to the grounded busycontact 220. The resulting closing of contact 219 again energizes secondary magnet SM. The relay l215 and magnet SM are thus alternately energized and de-energized lto step the Wlpers 209, 210 and'211 in a secondary rotary direction to seek the contacts of an idle connector switch as E. When a contactv 220 leading to an'idle connector .is encountered by the wiper 209, 4an energizing circuit of the relay 215 is not again closed, and no further energizations of the secondary, magnet SM occur. By this see-'saw action of relay 215.

and 'magnet SM Ia positive driving operation of the secondary magnet SM is secured and the selector D will not stop on a busy contact or go past an idle contact because unless'relay 215 is energized, magnet SMcanl'lU notbe energized, and relay 215 can only be v energized when magnet is atnormal and private Wiper' 209 isresting on abusy contact. The relay 200 does not de-energize during the secondary/movement of the wipers,- due to its adjustment and the rapidity energization closes a .circuit for thelower winding of the relay 200, aspreviously de- Iof the interruptions of Contact 212 of seci scribed, and 4due to its differential construe-2130 tion, it de-energizes, Whereon an energizing circuit for the relay T is established traced from battery through the winding of the said relay T, alternate contact 218 of the secondary off-normal contacts SON. normal contact 201, contact 204 to ground at 199. The opening of normal contacts 192 and 193 of relay T opens the energizing circuit of the impulse relay IR, and the closing ot normal contact 195 of said relay IR closes a circuit through the lower Winding of the relay 196 traced from battery through the said lower Winding, vnormal Contact 195, to ground at contact 208 of relay 196, which relay 196, due to its di'erential winding, neutralizes and restores to normal, and 196, opens the circuit of relay 200 permitting the latter to restore. The closing of alternate contacts 192 and 193 of relayT extends the connection of the calling subscriber A to the idle connection E, engaged by Wipers 209, 210 and 211 of the first selector: D, bringing about the energization of the impulse relayIR' of Connector Evover a circuit traced from ground through one Winding of the relay IR', contact 222, wiper 211, alternate contact 193, contacts 7--23, alternate contact 177, through the substation A, alternate contact 178, contact 22, alternate contact 192, contact 210, contact 221, and through the left hand Winding of the relay IR to battery and ground. The .restoration of the relay 196 of the first selector D. opens the initial energizing circuit of relay T at D, but the relay T being slow to release has a substitute circuit established for it, traced from battery through the Winding of said relay, its alternate contact 225, Wipery 209, bank contact 220, conductor. 226, and conductor 227 to ground at alternate Contact 228 of the impulse relay IR. The said relay T remainsenergized until the termination of the conversation.

The energization of the relayv IR energizes relays 229 and 230, the circuit of relay 229 extending from battery through the vright handv Winding of said relay, normal 'contact 231 ofthe primary off-normal contacts PON", conductor 226 and conductor 227 to-ground at alternate contact 228 of relay IR'. The circuit for relay 230 extends from battery through the lower Windin of the relay 230, conductors 231, 232, an alternate contact 233 to ground at alternate contact A228 of relay IR'. Relay '229 locks itself to ground at 234. Four impulses now transmitted from A de-energize 4and energize relay IR' four times causing the primary magnet PM' to energize and de-energize lfour times to step the Wipers 235; 236

' and 237 in a downward primary direction to the fourth group of contacts containing those of the called line., The circuit of the primary magnet PM' may beV traced :fromA battery through the Winding of the said magnet PM', normal contact 238 of switching relay SlV, lconductor 238. alternate contact 240 of rela-y 230, normal contact 233 of relay IR', conductor 227, conductor 226, through normal contact 231 of the primary of-normal'contacts PON' to ground at alternate contact 2340i relay 229. After the primary off-normal -contact 231 assumes its alternate position, Which occurs upon the first step of the switch shaft, thc ground fed from contact 241 of relay 242 is substituted for 'the ground fed through contact 234 of relay 229. After the last` impulse of the series has been sent, the steady flow of current through bothwindings of relay 230 causes the said relay 230, due to its differential action, to neutralize and restore its contacts to normal, but it does not restore during the sending of impulses due to its adjustment, construction and the rapidity of the interruptions of contact 233. The closing of` normal Contact 243 of relay 230 energizes switching relay SW by current through the Winiling of said relay SW, its make-beforebreak contact 244, normal contact 245 of seconda off-normal s rings SON. con-` ductor 246, normal contact 243 of relay 230, and conductor 247 to I,ground at alternate contact 248 of primary-otf-normal contacts PON",'and relay SW locks itself to ground via contacts 257 and 248. .The closing of alternate contact 238 of the switching relay .SlV merely substitutes secondary magnet SM foumagnet PM', so that When the calling subscriber at the substation A sends the last' set of" impulses, which I have assumed are five in number, relay IR' energizes magnet SM `five times, and secondary magnet 'SM' stepsthe Wipers 235, 236 and 237 in a secondary rotary direction tov engage contacts 250, 251 and 252 ofthe calledline; Upon the first impulse of the lastl set, the revlap-y 230-again energizes topermit the secondary magnet SM' to be operated, and after the last impulse the relay 230 is again (le-energized, as previously described, and

from battery, through the winding' of the said relay, conductor 253, thealternate contact 254,I alternate contact 245 of the secondary oit-normal contacts SON', (said con# 'private contact 250 of the called line would `be grounded, thus closing a locking circuit for ,the said relay TR through the private wiper.

-closes a circuit for the test relay TR tracedA 'a'lled Zz'ne idle.

Assuming that the'called line is' idle, private contact 250 of the called line4 will be free' of ground, and the relay TR will not remain energized but will cle-energize. The opening of normal contact257 of relay TR upon its momentary energization opens the circuit of the switching relay SW, and the relay SW de-energizing opens the circuit for relay TR at its contact 254, leaving the relay TR dependent upon the potential found upon the private contact 250 of the called line. Since, as assumed, this conalternate contact 274 of relay` 266, wiper 237, contact 252, through the now, closed 'upper contacts of the substation switch hook at the called substation F, back through -contact 251, wiper 236-alternate contact 275 of relay 266, and through the tact is idle and'thus free from ground, the\ upperwinding of the. relay SR. to ground.

-relay TR de-energizes and thereby causes the energization of relay 242 by current from battery, through the upper winding 183 of the cut-oli' relay CO', conductor 184', contact 182', conductors 185.', 186', and 187', private contact 250, through wiper 235, conductor 256, normal contact 255, conductor 258, normal contact 259 of relay-SW, conductor 260, through the lower winding of the relay 242, and conductor 261 to ground at 262. The closing of alternate contact 263 of relay 242 short circuits the'lower winding of the said relay, and the closing of its valternate contact 264^closes a circuit through the upper winding of the said relay through the alternatev contact 264 andV conductor 261 to ground at 262. The relay CO. of the line switch C associated with the called line F -attracts its armature but its movement is limited due to the arm 141 associated with its armature 106 resting inthe-notch 144 of 4lie latch 143 as Ipreviously described, but

is movement 4allows contacts 17 7 and 178 to move suiciently to open normal contacts 177' and 178 but not enough to close their. alternate contacts. This movement of contacts 177' and 178' removes ther substation control ofthe line switch C of the called line F. The other contacts of the relay CO' `are not affected due to this limited movement.

The closing of alternate contact 265 of relay 242 connects the interrupter I of the relay 266, circuit for relay 266 being traced from battery through relay 266, conductor 267, alternate contact 265, conductor 268,

normall contact 269 and through I .to ground. The relay 266 is thus intermittently energized and de-energized, and upon each de-energization rin ing generator RG is connected to the calle line over a c1rcu1t v extending from'the ungrounded pole'of the generator RG, through normal contact 270 The relay SR, upon energizing, closes an energizing circuit for the ringing control 'relay RC, which may be traced 'from battery through the winding of the said relay RC, its make-beore-break contact 277, t9 ground at 278. Contact 279 locks r'elay RC yfrom battery, throughthe winding of vthe said relayRC, its alternate contact 279 and conductor 247, to ground at alternate contact 248 of the primary offnormal contacts PON. The opening of normal contacts 269 and 270 disconnects vthe interrupter l and the ringing generator RG to' prevent further application of ringing current. A v

substitute circuit or'the relay'266 is now established which maybe traced from battery, through the winding of the relay 266, conductor 267, alternate contact 265, conductor 268, alternate contact 269 and conf ductor 247 to ground at 248.v The subscribers are now in conversationalcircuit, and

the talking circuit may be traced over the heavily marked conductors, said conductors having the condensers K' and K2 interposed. l

- Release.

ssuming that the subscriber at the callyl ou ing substation A is'the rst to replace his receiver, the resulting de-energization of'.

the impulse relay IR of theconnector E opens the holding circuit of the relay T otl the first selector D, and the-closing of normal contact'216 of relay T energizes relay 215 by current from battery, through said relay 215,v normal contact 216, normal contact 217, normall contact 223 and contact 214 to ground at 199. The closing of alternate contact 219 of relay -215' energizes secondary magnet SM, and the-relay y215v and secondary magnet SM 4are alternately energized and4 de-energized, (as before de-` scribed), the secondary magnet SM-lthus stepping the wipers` 209, 210 and v211 befr yond the last contacts of the row fof bank contacts, from whichpoint the wipersare restored to normal by spring tension.

The secondary ofnormal. contacts SON and primary off-normal contacts PON are restored to normal, and the opening of alternate contact 199 of the primary off-normal contacts PON opens the energizing circuit of the cut-olf relay CO of the findividualline switch C. The restoration of the cut-olf relay CO restores the individual switch C to normal.

The subscriber `F restoring his receiver upon its switch hook interrupts the circuit of the relay SR at the switch hook contacts, causing the said relay to de-energize. The closing of normal contactv 285 of relay SR closes a circuit through the left hand winding of the relay 229 which may be 4traced from battery, through the left hand winding of the said relay 229, alternate con?v tact 286, conductor 287, normal contact( 285 and conductor 288 to ground at normal contact 228. Due to the dierential construction of relay 229, the said relay neutralizes and restores to normal. The closing of normal contact 289 of relay 229 closes an energizing circuit for the secondary magnet SM', from battery, through said magnet, conductor 290, normal contact 289, contact 291, through the interrupter I to ground. The secondarymagnet SM thus steps vthe wipers 235, 236 and 237 beyond the last set 'of contacts in theV group, the wipers then restoring to normal from this. position by. spring tension. The restoration of the relay 229 opens the circuit of relay 242 at contact 262, and the relay 242 restoring opens the circuit of relay 266 at contact 265.. The primary` oH-normal contacts PON 'having restored upon the restoration of the switch, the opening of 'the contact 248 de-,energizes :relay RC. The relay 229 also brings about the deenergization of the cut-ofi` relay CO of the line circuit C which is associated with the called 'subscriber F.

All the apparatus used in establishing a connection between a calling .subscriber at the substation A and the called subscriber at the substation F is now at normal and available for use inf establishing other conn ections. l

.Assuming now that the subscriber at the called substation F. was rst to replace his receiver upon the switch hook, the opening of the switch hook contacts at the substation F brings about the de-,ener'gization of the relay SR. Nothing else happens'at this time as'the relay IR is still maintained energized over the line of the calling substation A. The calling subscriber at the substation A replacing his receiver interrupts lthe circuit of the impulse relay IR at the i same ,as previously described from this switch hook contacts. The relay IR deenergizing closes a circuit for the left hand winding of relay 229, causing the. said relay to de-energize, as hereinbefore described. The restoration of the individual switch C, first selector D and connector E is the ',ternatecontactl 228 of impulse relay IR opens the circuit of the relay T of rst lselector D as before described, and causes the release of selector D and individual line switch C.

The subscriber at the called substationl failing to replace his receiver, permits the continued energization of the relay SR, thus holding the Contact 285 of said relay in its alternate positionpreventing the diferential Vwound relay 229 from restoring ,to normal,

andl closing the energizing circuit for the secondary magnet SM. Thel relay 230 energizes'when the line relay LR drops back but is immediately restored to normal due to the closure of an energizing circuit through the lower winding of the said relay 230, which may be traced from battery, through the said lower winding, conductor 232, alternate contact 285, conductor 288 to ground at alternate contact 228 of; the now restored impulse relay IR. Relay 230 being di'erentially'wound, restores to normal and the closing of normal 1contact 295 of the said relay 230 places a ground upon the private contact of the connectorI E over a circuit which may be traced from ground at contact 248, conductor 247, normal con? tact 243 of relay 230, conductor 246, alternate contact 245, normal contact 295, alter-L nate vcontact 296 of the secondary olf-normal contacts SON to the'private contact U220.

A The placing of this busy potential upon the Yprivate contact prevents any irst selector switch D from selecting busy connector. y

calza; la@ busy.,

the contacts of this a locking circuit for the test relay TR from battery, through the winding of the said relay, its alternate contact 255, 'conductor 256, and the wiper 235'to thel ground-l ved contact 250. Alternate contact 297 ofthe test relay TR remains closed and connects the busy signalBB to the calling line to transmit signal to A, thus notifying the subscriber of the busy condition of the called substation F. Relay RC 'is also 'energized when connection is made to -a busy line toy prevent an application of rlnging current from being applied to the called line if 'the called line should become idle before the connector E is disconnected from the bank contacts of a called subscribers line. Therelay RC uponV energizing locks up through its own make-before-break Vcontacts 277 and' 279 to ground at alternate contact 248. The calling subscriber no-w replaces his receiver, bringing about the delenergization of the impulse relay IR', and

the relay IR restoring, opens the circuit of the relay T of the lirst selector D, which,

as previously described, brings about the release of the first selector D and the individual switch C. The relay IR de-enercizing, restores relay 229, (since the relay @It has not been energized) and by the closing of circuit through the left hand winding ot said relay 229, the closing of Contact 289 now connects secondary magnet SM and interrupter I', and the connector restores to normal by spring tension. The primary off-normal contacts PON andk secondarv oit-normal contacts SON` are also restored,`

and all the apparatus used is now ,at normal and available for use in establishing other connections. f

While I have shown a system of 1,000 ca-v pacity, itis to be understood that by inserting second selectors, the system may be `increased to a 10,000 system, etc.

It is to be understood that I do not wish to be limited to the matter shown, `as various other arrangements will -readily suggest themselves toy one skilled in the art, and

the invention may be used in a wide variet of circumstances and relations.

What -I claim as new and desire to secure by United States Letters Patent, is:

1. An automatic telephone system including a traveling switch and an adjusting -magnet therefor, and a relay initially energized by current flowing over the. talking circuit and thereafter serving in vibratory relation with themagnet', andl test means -servingwhen in a particular electrical condition, to render the initial energization of said relay ineffective to set up said relal tion.

2. An automatic switch including a relay and magnet in vibratory relation, said relay initially energized by .current over the talking circuit and thereaftergby 'current over a local circuit, and test means serving when in a particularelectrical condition, to render the ini-tial energization of said relayineec'tive to set up said relation. v

3. Inan automatic telephone system .a rei lay initially energized 'in series with a subscribers -line and thereupon automatically' disconnected from said line, a switch-ad justing magnet in vibratory relation with lsaid relay, and test means serving when in a particular. electrical condition, vto renderl the initial energizati'onof said relay ineffective to setup said relation.

4. A telephone system including a line ticularelectrical' condition to prevent an initial operation of said relay from energizing j --said magnet.

5. A telephone system including a telephone line, a source of current connected across the talking circuit thereof, a step-bystep vibratory magnet adapted when ener-v gized to open its armature contact to disconnect.a Side of said. source from said line,

a line relay connected-between said. source and said line itsl circuit including said contact, a'nd local test means serving when in a particular electrical condition to prevent an initial energization of said magnet when the talking circuit is closed, and in another condition to permit suchenergization.

L 6. A selecting llsystem including a line relay and switch controlling magnet both con-l nected tothe same test circuit during switch adjustment, and when so connected in vibratory relation oneV with the. otherand a slow pull-up relay, its .circuit intermittently. closed' duringl the vibratory operation, but

actuating only at cessationof operation.

7, A selecting system lincluding a yline 'l relay and switch. controlling magnet both v connected to the same test circuit during the switch adjustment, and when so connected in vibratory relationone with the other and a F- slow pull-up relay, its circuit rintermittently closed during the vibratoryy operation, Ibut actna'ting'only at cessation of operation and switch contacts'controlled'thereb whereby and said magnet.

8.l A. selecting system including a line relay-and a switch controlling magnet, both connected'to the test Wiper .of the switch during selection, and in'vibratory relation with each other.

9. A selecting system including a relay to. I

be energized by current over a subscribers line, a step-by-step magnet' in vibratory resaid magnet, a second relay automatically operatedzto alter said relation, and local test means serving when in a particular electrical -condition, to render the --1n1t1al energiza- 105- -said test circuit is freed from lsai first relay f tion' of said relay. ineffective to set up said relation.

10. The 'selecting system comprising 'a switch adjusting magnet and a relay, both" energizedv one after the other, by current traversing' a test wiper when said wiper is connected toa circuit in an abnormal electrical condition. f

' 11. A selecting system-'including a test i circuit switch devices namely, a relay and a.

lation with said relay, andsaid relay with an armature, tri

switch adjusting magnet, connections from said circuit to said devices, the connection to the one device including a normally open contact controlled b the other device and the connection to sai other device including1 a normally closed contact controlled by sai one device, and means for connecting said test circuit successively to a plurallty' of c1r' cuits'to be tested.

12. A telephone line and switch therefor, a line relay connected to the line and operated by current in said line, an adjustment controlling magnet for the switch, means whereby said relay and magnet operate in vibratory relation witheach otherl and test contacts, said magnet being responsive to the ynormal or abnormal electrical condition of said contacts on initial energization of said line relay to determine whether or not said lvibratory relation shall be set up.

13. A non-restoring, non-numerical line switch havinga line relay and a vswitch adjusting magnet, said line relay serving in vibratory relation with said magnet. A

14.. A line switch-having a line relay and a switch adjusting magnet, an armature contact of said magnet in the circuit of said relay, an armature contact of said relay in the circuit of saidV magnet, and connections for energizing said magnet, including a traveling contact maker connected to said first mentioned contact.

15. A line switch, having a line relay and a switch-adjusting magnet in see-saw relation while said switch travels, a trip contact shifted by the relay armature on its energization, and a line cut-off relay energized on selection made to restore said contacts.

16. A Ime switch, including a line relay, contacts shifted by lsaid armature on initial energization or' said relay', one of said contacts being in the circuit with the winding of'said relay, and a 'li-ne cut-01T l relay actuated .on selection to lace said contacts in normal relation.

17 In a line switch for automatic exchanges or the like, a line relay and la line cut-oil' relay, trip contacts 'shifted by said line relay and restored by said cut-oil' relay and means controlled by' said line relay and effective unless said contacts are in tripped condition to revent the. complete operation of said cut-o relay.-

18. In a: line switch for automatic exchanges or the like, aline relay and adoublewound line cut-olf relay, an energizing circuit lfor said cut-olf relay including one of the windings'ofsaid double wound cut-oli' relay, a locking circuit for said cut-off relay includingthe other winding of said double wound cutoli relay, mechanism normally lpermitting a partial operation only of the 'armature' of said vcut-off relay, means controlled by -said vline relay when energized to permit a full operation of said armature,

AIIJIJ and means controlled by the restoration of the armature of said cut-0E relay to place said mechanism in normal position.

19. In a line switch -circuit a line relay, a trip contact actuated by said relay on energization to disconnect said relay from the line, and a line cut-olf relay restoring said contact on selection made. 20. In a line switch, a double-wound line cut-off relay, an energizing circuit for saidv cut-olf relay having a normally partially blocked armature and a normally caught trip contact and armature mechanism for the line relay to unblock said armature and trip said contact.

22. In a line switch a line/cut-oi relay,.

a contact mounted on the heel iron of said relay operable at all times by said relay,

another contact on said relay operablel by said relay only when said switch is used to 'extend the calling line, and a catch con-.

trolled by said line relay for placing said second contact under the control of said cut-off relay.

23. In a line switch, a line relay, a line cut-olf relay, a switch contact solely controlled by -the line relay, a switch contact -solely controlled byy the cut-oiil relay, al

third switch contact secured tothe heel iron of. one of said relays and jointly controlled by said relays, anda catch controlled'by im said line relay for placing said third switch contact under the control of said cut-olf relay.

24. In a line Switch, a line relay and its l armature, a line cut-olf relay, a .switch contact shifted by said cut-oil relay and a catch to hold it in shifted position, mechanism of said line relay, operable to release said catch, a relay contact of said cut-off relay, said mechanism of said line relay serving in one position to permit a partial excursion of' said contact only, and in another p jion a full excursion. thereof, and circul s of l said switch connected to said contacts.

. 25. In'aline switch, a line cut-olf relay'` a switch contact secured to the heel iron 'thereof and lunder the sole control of vsaid relay, aline relay and switch contact of said cut-olf relay operatively `controllable by said cut-olf relay only after an operation of said line relay, and a catch controlled .by

said line relay for placing said second'contact under the control 'of said cut-olf relay.

.26. In a line switch, a line cut-olf relay? a switch contact thereof under sole control of said relay, a line relay, a switch contact of said cut-ofi' relay and interlockingmecha- Anism requiring operation pf both relays to render sald second switch contact effective, 'I v t ,energlzation to disconnect said relay from and a catch controlled by said line relay for placin said second contact'under the control .of sai cut-o relay. 27. A relay 'combination including two relays and their inter-locking armature mechanism, two switchcontacts and a shifting lever for each, said levers actuating by the energization-of the first relay, a member.

normally holding one lever in a position to which it is moved by the energization of the n first relay, said member controlled by the second relay to release said lever, a second member normally preventing a full excursion of the other lever but permitting a artial excursion thereof, said second mem- Eer controllable by said secondy relay tol permit the full excursion.

28. An automatic telephone system including a traveling switch and an adjusting magriet therefor, 'and means serving when ina particular 'electrlcal conditlon, to render the-lnitlal energization of said relay ineective'to set up said relation. g

29. In a line switch circuita linevrelay, a tripl contact' actuated by said relay on the liIe, and' a line said Contact. I 30. A system of the character described lncluding va non-numerical',l non restoring linev switch provided with a pair ofmagnets, lcircuits for each of said magnets eX- tending through lthe lcontacts of eachother,

cut-.oil relay restoring.

a double-Wound vcut-olf relayhavin'g its energizing circuit extending through one of said contacts, said energizing circuit 'includ- -mg one windingof said double Wound cut.

oil relay, and a elocking circuit for said cut-oli relay. including the. other winding of said cut-oft' relay. v

Signed by me at Chical 0,'in the county f of Cook, andl `State of I in'ois, this -16th day of January, 1919.

HARRY H. rDE. 

